Metatron's Cube

Metatron's Cube enters the battlefield tapped.
Whenever you draw a card for the first time each
turn, put a divinity counter on Metatron's Cube
for each card draw this way.
{10}, Remove 50 divinity counters from Metatron's
Cube and sacrifice it: Draw cards equal to the
number of cards in your library minus 10. You
may play cards from your hand without paying
their mana cost until end of turn.